Features: Selection of high quality stainless steel, anti-corrosion and rustproof. Ceramic bearing balls have low friction coefficient, which move smoothly and flexibly. The bearing balls are sealed with rubber material, waterproof and dustproof, safe to use. High strength metal construction, durable with long service life. Specially designed for fishing line reel. Specification: Model: S623C-20S Inner Diameter: 3mm Outer Diameter: 10mm Thickness: 4mm Bearing Material: Stainless steel bearing ring + ceramic ball Seal Material: Rubber Quality Grade: ABEC-7 Weight: 2g (approx.) Package List: 1 x Bearing Package List 1Selection of high quality stainless steel, anti-corrosion and rustproof. 2Ceramic bearing balls have low friction coefficient, which move smoothly and flexibly. 3The bearing balls are sealed with rubber material, waterproof and dustproof, safe to use. 4High strength metal construction, durable with long service life. 5Specially designed for fishing line reel.